Lake Powell inflow projected to be less than half of average
By Summit Voice
SUMMIT COUNTY — Federal water managers have significantly lowered their expectations of runoff into Lake Powell this year in the past couple of months, as a lack of spring snowfall and an early snow-melt season combined to shrink the snowpack in the Upper Colorado Basin to just a third of average.
March inflow into the key reservoir was about 10,000 acre feet higher than forecast, mainly due to the early snow-melt season, but still only 84 percent of average. Through July, the inflow is only expected to be 49 percent of average. For the water year, the inflow is now projected to be about 63 percent of average.
That marks a setback in regional water storage, which saw improvement since 2005, following a string of dry years. Between 2005 and 2011, Lake Powell’s inflow was 101 percent of average, thanks in particular to the 2011 water year, when inflow peaked for the period at 147 percent of average.
From BuRec’s Lake Powell website:
Overall reservoir storage in the Colorado River Basin has increased by over 8 maf since the beginning of water year 2005 and this is a significant improvement over the drought conditions during water years 2000 through 2004. On October 1, 2004, the beginning of water year 2005, the total reservoir storage in the Colorado River Basin was 29.84 maf (50.2% of capacity). On October 1, 2011, the beginning of water year 2012, the total reservoir storage in the Colorado River Basin was 38.66 maf (64.8% of capacity). As of April 3, 2012 the total reservoir storage in the Colorado River Basin was 37.53 maf (62.9% of capacity).
How dry has it been lately? The Boulder office of the National Weather Service says the combined official snowfall total for March and April was 1 inch — the lowest combined March-April Snowfall on record dating back to 1882. The previous low was 1.1 inches in 1887.
The average is 20.5 inches. This marks the second year in a row that combined March and April snowfall has been less than 5 inches. Dating back to 1882 there has never been two consecutive years where the combined March-April Snowfall was less than 5 inches.